SAN ONOFRE OPERATOR WANTS TO OPEN PLANT IN JUNE

If technical analysis holds up, proposal to go to feds in May

The operator of the troubled San Onofre nuclear plant said Thursday that it plans to seek federal permission to restart its two idled reactors — at reduced capacity — in June.

The seaside plant has been offline since January after the discovery of a leak in one reactor’s steam generator tubing and rapid degradation of the tubes in both reactors.

Stephen Pickett, executive vice president for Southern California Edison, said if the company’s current technical analysis holds up, the reactivation proposal would be presented to regulators in mid-May. That could conceivably lead to a restart of the northern reactor by June 1 but probably mid-June, he added.

The southern reactor, which has shown more significant wear on its tubes, would follow one to three weeks later, Pickett said.

Both units would operate at low power, reducing the flow of heated water through generator tubes in an effort to minimize destructive vibrations. The reactors’ generators would be re-examined ahead of the normal 18-month refueling schedule.

“We have homed in on the cause of the tube wear and believe that we have a proposal,” Pickett said in an interview. “If the technical analysis continues to hold up, we would present that to the (Nuclear Regulatory Commission) in mid-May.”

Shaun Burnie of Friends of the Earth, an international organization that scrutinizes the nuclear-power industry, accused Edison of trying to manipulate regulators with its timetable.

“Edison is clearly aiming to put enormous pressure on” the commission, said Burnie, whose group commissioned an analysis highlighting problematic design changes when San Onofre replaced its generators starting in 2009.

“But it runs into reality,” he said. “There are fundamental issues that have yet to be explained, yet to be understood and yet to be presented to the (commission), never mind to the public and politicians in Southern California.”

Southern California utilities and electrical-grid operators are scrambling to line up enough power and conservation commitments to meet peak summer demand, which could come as early as June with a heat wave. Initial power estimates show San Diego County has the state’s tightest supply margins, with some potential for rolling outages under unusually hot conditions.

The state’s main grid operator, the California Independent System Operator, said Thursday it is continuing with its contingency plans for a summer without San Onofre, including efforts to bring retired generators back online.

Edison and the Nuclear Regulatory Commission have emphasized that safety is the first priority in addressing the rapid wear in steam-generator tubes at the plant. Tube leaks or ruptures at pressurized water reactors like San Onofre can lead to the release of radiation into the atmosphere and eventually threaten a reactor’s core cooling system.

A tiny radiation leak on Jan. 31 at San Onofre — regulators said it presented no danger — was traced to a steam tube leak in the southern reactor, triggering its shutdown. The northern reactor was already offline at the time for scheduled maintenance and refueling.

Nuclear regulators said Thursday that they have received no direct notice of Edison’s new plans and said the company will be held to its detailed safety commitments outlined in a March “action letter.”

“As far as the (commission) is concerned, they will need to demonstrate that they have identified the cause or causes of tube degradation and have taken steps to ensure that it won’t recur if they start up,” said Victor Dricks, a spokesman for the agency.

An augmented inspection team sent from the Nuclear Regulatory Commission’s central and regional headquarters in Maryland and Texas has not concluded its work at the plant.

The two reactors’ steam generators were replaced at a cost of $670 million. Edison has spent between $55 million and $65 million on repairs as of the end of March, according to quarterly financial statements filed Wednesday. San Diego Gas & Electric owns 20 percent of San Onofre.

Edison said it may try to recoup some of the costs from generator manufacturer Mitsubishi Heavy Industries.

Pickett said Edison has ruled out shipping, installation and operation of the replacement generators as a root cause of the tubing problems.

“We haven’t come to a final conclusion yet, but we are thinking that this is probably a design defect,” he said. Federal regulators are still reviewing Edison’s secondary oversight role in the design and manufacturing, he added.